• Title/Summary/Keyword: Retention rate

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A Study on the Elution Behavior of Pd-Isonitroso ethylacetoacetate imine Chelates by Reversed-phase High Performance Liquid Chromatography (역상 고성능 액체 크로마토 그래피에 의한 Pd(II) - isonitrosoethylacetoacetate imine 유도체 킬레이트의 용리거동에 관한 연구)

  • Kim, Hyun
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.19 no.1
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    • pp.20-30
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    • 1993
  • Liquid Chromatographic behavior of Pd(II) in Isonitosoethylacetoacetate imine IEAA-NR: R=H, CH3, C2H5, n-C3H7, n-C4H9, C6H5-CH2) Chelates were investigated by reversed phase high performance 1iquid chromatography on Micropak MCH-5 Column using Methanol /water as mobile phase. The optimum condition for the separation of Pd-Isonitrosoethylacetoacetate imine chelates were examined with respect to the flow rate, mobile phase strength. It was found that Pd(IEAA-NR)2 chelates were eluted in an acceptable range of the capacity factor value (0 $\leq$ log k' $\leq$ 1), The dependence of the logarithm of capacity factor(k') on the volume fraction of water in mixture with in the binary mobile phase was examined. Also, the dependence of k'on the liquid-liquid extraction distribution constant in methanol-water / n-alkane extraction system was on system was invert tigated for Pd(IEAA-NR)2. Both kinds of dependence are linear, which suggests that the retention of the electroneutral metal chelates be largely due to the solvophobic effect.

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A Study on Urinary Incontinence of Elderly Communities (지역사회 거주 노인의 요실금에 관한 연구)

  • Ju, Young-Hee;Kim, Jung-Soon
    • Research in Community and Public Health Nursing
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    • v.11 no.2
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    • pp.441-452
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    • 2000
  • The purpose of this study was to identify the prevalence of urinary incontinence and its relating factors elderly communities. Subjects of this survey consisted of 877 elderly women and men in one Kun. Korea, who were over 60 years old. The design for this study was descriptive: the subjects were interviewed by well trained investigators from July 9. 1999 to July 20. 1999. During that survey period, the subjects were interviewed with a structured questionnaire. The data were analyzed by frequency, percentage, $X^2-test$. T-test using an SAS program. The results of the study were the following: 1. The prevalence rate of urinary incontinence was 20.1 %. of the total. The types of urinary incontinence were mixed incontinence 44.3%. stress incontinence 38.1%. and urge type incontinence 17.6%. 2. The relating factors of urinary incontinence were as follows: 1) 33.5% of UI(urinary incontinence) subjects reported urine loss once a month. twice or three times a week 23.3%. one or two times a day 17.0% 2) 38.1% of elderly reported only 1 to 2 drops. 1 t-spoon 36.9%. 1 T-spoon 15.9% 3) The volume of urine loss registered by changing underwear was 63.1 %. no necessity of changing underwear was 22.1 %. or using some type of pads was 13.1%. 4) 62.5% of UI subjects never discussed their UI problem with other people. 73.9% of the total had never experienced any treatment for their UI problem. The reasons for not receiving medical cure were their typical conception about urinary incontinence taking UI as a normal part of aging 76.2% and due to their bad financial situation 9.2%. 3. Women had more prevalence of UI than men (p=0.01), and it was found that the worse the subjective health state. the higher the prevalence of UI (p=0.001). However. there was no statistical difference in daily frequency of UI (p>0.05). The more nocturnal incontinence (p=0.001), the more intermittent stream experience (p = 0.01), the more retention experience (p = 0.01), and the more incomplete the emptying experience (p=0.001), the higher the prevalence of UI. 4. UI groups had lower ADL scores than non UI groups(p=0.01). The level of depression in the group of urinary incontinence was significantly higher than that of non incontinence group (p=0.0001). As shown above, the elderly people suffering from UI haven't been treated properly: their subjective health state and their ADL competence was lower, and their depression level was higher than non UI groups. Therefore, the development of a proper urinary incontinence management program are required so that they can lead more healthy lives. Also continual case studies for the elderly people with UI are necessary.

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Evaluation of Patients with Rheumatoid Arthritis by Tc-99m MIBI Imaging (류마티스 관절염환자에서 Tc-99m MIBI 영상의 유용성 평가)

  • Cho, Ihn-Ho;Chun, Kyung-Ah;Hong, Young-Hoon;Lee, Choong-Ki;Ha, Jeung-Hee
    • The Korean Journal of Nuclear Medicine
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    • v.38 no.6
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    • pp.506-510
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    • 2004
  • Purpose: We investigated whether Tc-99m MIBI imaging is useful to predict the response of drug treatment in patients with rheumatoid arthritis. Materials and Methods: 24 patients (15 women and 9 men, age $49{\pm}12$ year) rheumatoid arthritis and treated with disease modifying antirheumatic drugs (DMARDs) were included in this study. Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were measured, and Tc-99m MIBI scan was obtained before drug treatment. Quantitative analysis of uptake in diseased joints was performed and expressed as joint-to background ratio (J/B) and percent retention (%R) of Tc-99m MIBI. Clinical symptoms were evaluated and graded from 0 (no) to 3 (severe) regarding to presence of tenderness and swelling. Results: J/B of the diseased joints were significantly correlated with ESR and CRP (p<0.05). A highly significant correlation was found between the improvement of clinical symptoms and %R of Tc-99m MIBI (p<0.05). Conclusion: The results demonstrate that Tc-99m MIBI scan may be used to predict the therapeutic response in patients with rheumatoid arthritis.

A Cross-Cultural Investigation on the Effects of Physical Environment at University Dormitory on Social Interaction among Students (문화적 배경에 따른 대학기숙사 물리적 환경이 학생들간 사회적 교류에 미치는 영향 비교연구)

  • Kim, Wonpil
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.8
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    • pp.48-54
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    • 2017
  • University dormitories play an important role in both the campus experience and academic achievement, as well as providing the students with their basic necessities. Further, there is a high demand to increase the capacity in order to raise the retention rate and to invite more foreign students. Students' social interaction and sense of community (SOC) also play an important role in reducing the stress associated with studying and home sickness and, consequently,the campus is a place that provides positive opportunities for their personal growth and adaptation into their peer group social culture. The purpose of this study is to investigate the effects of the physical environment of the dormitory facilities on the students' sense of community and social interaction in across-cultural background.The ${\chi}^2$ analysis indicated that individual characteristics exist regarding SOC, however, there were no statistically significant differences between the two cultural groups. The factors of SOC and physical environment were higher in the Korean student group than in the U.S. group. The regression analysis indicated that the U.S. students considered a physically comfortable environment as the primary issue for social interaction, while the Korean group placed more emphasis on a family-oriented home environment. The linear analysis confirmed that satisfaction with the physical environment influenced the social interaction and SOC level. Finally, this study suggests that creating a homely environment is more important than the functioning of the institution in university dormitory planning.

Surgical Treatment of Esophageal Perforation (식도천공의 외과적 치료)

  • Park Jae Hong;Chei Chang Seck;Kim Dae Hwan;Hwang Sang Won;Yoo Byung Ha;Kim Han Yong
    • Journal of Chest Surgery
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    • v.39 no.3 s.260
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    • pp.214-219
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    • 2006
  • Background: Perforation of esophagus is relatively uncommon. but it is associated with high morbidity and mortality. Treatment and outcome are largely determined by the time of presentation. We performed a retrospective review of patients with esophageal perforation to assess the outcome of current management techniques. Material and Method: A retrospective chart review was performed on all patients treated for perforation of esophagus from March 1990 to March 2005. There were 28 patients (22 men and 6 women: mean age 51 years, range 17 to 82 years) The causes of the perforations were as follows: foreign body retention (9 patients), trauma (7 patients), spontaneous rupture (7 patients), and iatrogenic (5 pati-ients). 18 patients were presented within 24 hours and 10 patients were presented after 24 hours., Esophageal repair was performed in 21 ($75\%$) of them, 4 patients were treated with esophagectomy, 3 patients were treated with feeding gastrostomy and drainage. Result: Hospital mortality was $18\%$ and iatrogenic was increase the mortality rate (p < 0.05). Site of perforation, time from perforation, and treatment method had no influence on mortality. Postoprative leaks occurred in 4 patients after primary repair and were treated conservatively. Conclusion: Esophageal perforation remains a devastating event which is difficult to diagnose and manage. Primary repair can be performed in most patients with esophageal perforation regardless of time to presentation with a low mortality. Accurate diagnosis and early treatment are essential to the successful management of patients.

Study on the Applicability Analysis of HPLC for Fuel Marker (Unimark 1494DB) in Petroleum Products (석유제품의 식별제(Unimark 1494DB) 분석을 위한 HPLC 적용가능성 분석 연구)

  • Hwang, In-ha;Youn, Ju-min;Doe, Jin-woo;Park, Tae-seong;Kang, Hyung-kyu;Ha, Jong-han;Na, Byung-gi
    • Journal of the Korean Applied Science and Technology
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    • v.34 no.4
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    • pp.1076-1084
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    • 2017
  • For analyzing the qualitative and quantitative analysis of fuel marker in petroleum products, the applicability of HPLC was studied. For the qualitative analysis of fuel marker in kerosene and automotive diesel, optimal analytical conditions(ratio of mobile phase solvent, flow rate, etc) in HPLC were selected and calibration curve for quantitative analysis of fuel marker was prepared based on the result of qualitative analysis. In particular, the correlation coefficient of calibration curve in kerosene and automotive diesel was shown to be 0.999 in a certain concentration range and it could be applied to the quantitative analysis. The results of analysis using the UV/Vis spectrometer, which is the current analysis method of fuel marker, were compared with the analysis results using the HPLC. The kerosene showed a low deviation of about 7 % and the automotive diesel showed a somewhat large deviation of about 20 %.

A Comparative Study on Institutional Influence Factors of Firm's Motivation of Participating and Investing in Apprenticeship in Germany and Korea (기업의 도제훈련 참여 및 투자 동기의 제도적 영향요인: 독일-한국 비교 연구)

  • LEE, Hanbyul
    • Korean Journal of Comparative Education
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    • v.27 no.1
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    • pp.247-284
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    • 2017
  • The purpose of this study is to analyze firm's motivation of participating and investing in apprenticeship in Germany and Korea, and to investigate institutional factors influencing firm's motivation. By comparing institutional factors of the two countries, it aims to drawing out policy implications for improving Korean apprenticeship. The main method for data collection was comprehensive literature review on international organizations, each countries' government and research institutes' policy materials, statistical data, research outputs and media resources related to each countries' apprenticeship. Considering whether firm's motivation for participating and investing in apprenticeship is production-oriented or investment-oriented, Germany is more inclined to investment motivation with firm's covering net cost during apprenticeship period. On the other hand, Korea is more inclined toward production orientation with firm's expectation of gaining net profit during the training period. Why is firm's training motivation different in these two countries? The author tried to find the reason from the difference of institutional factors of the countries by dividing institutional factors into 4 categories: context(tripartite relations, legal framework), input (flexibility of the system, government incentive), process(training contents, training duration, quality assurance), and output(completion/retention rate, apprentice's productivity). The key implication from the comparative analysis of institutional factors is that it is necessary to enforce companies to have "accountability" on the minimum critical elements, but also to ensure them to have "autonomy" on the rest of the elements.

Preparation and Properties of Water-based Adhesive Using Gemini Type Nonionic Reactive Surfactants (제미니형 비이온 반응성 계면활성제를 이용한 수성접착제의 제조 및 특성)

  • Shin, Hye-Lin;Jeong, Noh-Hee
    • Applied Chemistry for Engineering
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    • v.30 no.5
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    • pp.597-605
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    • 2019
  • In order to improve the adhesion of water-based adhesive, gemini type nonionic reactive surfactants were synthesized and applied to water-based adhesives. The surfactants were synthesized by using maleic acid and polyoxyethylene cetyl ether having different length of ethylene oxide and confirmed by FT-IR and $^1H-NMR$. Their appearance was light yellow wax. The cloud point of the compound was more than $78^{\circ}C$. The measured critical micelle concentration (c.m.c) was $1.0{\times}10^{-4}{\sim}7.0{\times}10^{-4}mol/L$ and surface tension at c.m.c was 25.9~32.0 mN/m. As the number of ethylene oxide increased, the emulsifying power was improved. The foaming height of each compound by Ross-Miles method was 1.4~4.5 cm. The synthesized surfactants was then used as an emulsifier in emulsion polymerization of water-based adhesives and its physical properties were evaluated. The solid contents of prepared adhesives was 59%. The average particle size and initial tackiness of the prepared adhesives were 164~297 nm and ball no. of 20~32, respectively. The peel strength was $1.8{\sim}2.1kg_f/mm$. The retention rate of adhesives viscosity was evaluated to 99% during 30 days. Therefore, synthesized gemini type nonionic reactive surfactants are expected to be applied as an emulsifier for the high adhesive force.

Watershed Water Quality Management Plan Using SWAT and Load Duration Curve (SWAT와 부하지속곡선을 이용한 유역 수질 관리방안)

  • KAL, Byung-Seok;CHO, So-Hyun;PARK, Chun-Dong;MUN, Hyun-Saing;JOO, Yong-Eun;PARK, Jae-Beom
    • Journal of the Korean Association of Geographic Information Studies
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    • v.24 no.3
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    • pp.41-57
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    • 2021
  • This study evaluated the application of water quality management measures using the SWAT model and the effectiveness of the measures using the load duration curve targeting the Seohwacheon watershed located upstream of Daecheongho. As water quality management measures, artificial wetlands, reduction of neglected livestock, reduction of runoff from greenhouses, restoration of ecological rivers, application of LID technology, and management of point sources were applied. The applied technology evaluated the efficiency of water quality improvement measures by using the target water quality excess rate and the degree of load reduction for each sulfur through the load duration curve. The load duration curve was created by creating a long-term flow duration curve using SWAT and multiplying it by the target water quality. For the target water quality, the value corresponding to the 60th percentile was set as the target water quality using the 10-year data from the Okcheoncheon water quality observation point located in the downstream of Seohwacheon. Through this study, it was possible to confirm the applicability of various water quality measures through the SWAT model, and to examine the applicability of each period according to the sulfur through the load retention curve.

Effect of Chronic Toxicity by Waste Microplastics (PET) on Daphnia magna (폐 미세플라스틱(PET)의 물벼룩 만성독성 연구)

  • Han, Bomi;Park, GeonU;Yoo, Seungwoo;Kim, Changhae;Jung, Jinho;Na, Joorim
    • Ecology and Resilient Infrastructure
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    • v.8 no.4
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    • pp.281-289
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    • 2021
  • Commercially used disposable cups undergo fragmentation in the environment and become microplastics (MPs). These MPs can be ingested by aquatic organisms and cause a range of adverse effects. We assessed the acute and chronic toxicity of disposable cup-derived MP fragments in Daphnia magna. MP fragments were identified as a polyethylene terephthalate (PET) fragment with a size of 33.18 ± 7.76 ㎛. The presence of three additives including 1- Propanone. 1-phenyl-3-[2-(phenylmethoxy)phenyl]-, p-Xylene and ethylbenzene was analyzed from MP fragments. The 48 h acute toxicity revealed that 20 % of immobilization and mortality were found at the highest concentration of PET MP (200 mg L-1). The 21 d chronic toxicity revealed that PET MP fragments significantly (p < 0.05) more reduced survival rate (31 %), total offspring (52 %) in D. magna compared with control group. The developmental abnormality of offspring (3.5%) by PET MP fragments was significantly (p < 0.05) higher than control groups (0.3%). These results are possibly induced by gut blocking by ingestion of MP fragments and their longer retention time. These findings indicate that the fragmentation of disposable cups (PET polymers) into small-sized MP fragments pose a significant ecological risk to aquatic organisms. Further studies are required to elucidate the underlying toxicity mechanisms.